audiocommon: remove 1:1 interpolation

The usual one is 32->48 khz interpolation. So there is no need in a special 1:1 interpolation only for performance.
audiocommon: sync mixer by fifo instead of estimate values
controll the interpolation frac by the fifo size
change AI sampling rate based on framelimit
Disable framerate correction for OpenAL

OpenAL itself stretch the time on slowdowns, so the Mixer isn't allowed also to change the rate.
Merge pull request #42 from degasus/latencyFix

audio latency fix